COMPACTION SIMULATOR STUDY OF A NOVEL TRIPLE-LAYER TABLET MATRIX FOR INDUSTRIAL TABLETING

The compression behavior and compactibility of a novel triple-layer ta blet formulation has been studied and the effect of punch velocity (50 mm s(-1), 125 mm s(-1), 250 mm s(-1), and 500 mm s(-1)) on the compac tion properties was also investigated using compaction simulator. The main formulation components were poly(ethylene oxide) (PEG), lactose, and theophylline. Heckel profiles of each layer as well as the combine d layers were constructed, the porosity and tensile strength of the co mpacts were determined, and strain rate sensitivity (SRS) values were calculated. Results indicate that the formulation of each layer and th e combined triple-layer tablet exhibited similar compression behavior, and the consolidation mechanism was shown to follow predominantly pla stic deformation as evidenced by the shape of Heckel plots and high SR S values. The strain rate sensitivity for layer 1, 2, and 3 and combin ed triple-layer tablet was 16.2%, 26.1%, 19.3% and 10.7%, respectively . The degree of compact densification and resistance to compressibilit y within the die cavity was influenced by production rate as evidenced from percent porosity reduction with increasing compaction pressure a s well as varying punch velocity. Compact lamination was only observed at both high punch velocity (500 mm s(-1)) and compaction pressure. F urthermore, changes in tensile strengths and residual porosity as comp ression force was increased showed similar trends at constant punch ve locities. It might be concluded that a successful design of triple-lay er tablet formulation necessitates careful selection of plastic, britt le, and other desirable components to ensure comparable compactibility profiles. (C) 1997 Elsevier Science B.V.